The NAACP argued that Plessy v. Ferguson was a violation of which amendment that offers equal protection under the Constitution?/

13th

14th

15th

16th

I feel like its the 15th but I'm not sure ... (?)

The correct answer is "14th".

Plessy vs Ferguson was a legal case in 1896 in which the US Supreme Court ruled in favor of upholding segregation laws for the use of public facilities as long as they offered the same quality. This policy was known as "separate but equal".

Many years later, the National Association for the Advance of Colored People (NAACP) started taking legal actions against this policy, stating that it violated the 14th amendment of the US Constitution, as it is not offering "equal protection for laws" that the 14th amendment requires to.

actually, i'm pretty sure its the 14th amendment.